Question

A thrust reversing system is used in jet engines to provide extra braking force to slow down an aircraft after a landing on a runway. The same concept is used to design an �air momentum brake� (AMB) system for a �high tech� racecar. The AMB system is activated simultaneously with the usual hydraulic brakes by opening an air-scoop to pull in and then deflect the high-speed air forward at 60 degree angle through the symmetric side opening as shown in the figure below. The aerodynamic design dictates a maximum inlet area of 5 ft^2 for the front air scoop. Exit area for each side opening is 1.75 ft^2. Use the systematic methodology to predict the AMB generated brake force acting on the racecar when it is traveling at 250 mph. The ambient air temperature and pressure are 60 F and 14.7 psia, respectively.